scholarly journals Incorporation of biogenic zinc nanoparticles in a polymeric membrane: Potential impact on the capture of organic herbicides

2021 ◽  
pp. 100339
Author(s):  
Salma Shad ◽  
Nadia Bashir ◽  
Marie-France Belinga-Desaunay Nault ◽  
Iseult Lynch
Keyword(s):  
Membrane Potential ◽  
Polymeric Membrane ◽  
Zinc Nanoparticles ◽  
Potential Impact

Measurement of spontaneous neuronal membrane activity by time lapse confocal microscopy

1995 ◽  
Vol 53 ◽  
pp. 972-973
Author(s):  
R H. Selinfreund ◽  
A. H. Cornell-Bell
Keyword(s):  
Membrane Potential ◽  
Confocal Microscopy ◽  
Patch Clamp ◽  
Electrical Activity ◽  
Time Lapse ◽  
Neuronal Firing ◽  
Neuronal Membrane ◽  
Pituitary Cells ◽  
Patch Clamp Recording ◽  
Spontaneous Electrical Activity

Cellular electrophysiological properties are normally monitored by standard patch clamp techniques . The combination of membrane potential dyes with time-lapse laser confocal microscopy provides a more direct, least destructive rapid method for monitoring changes in neuronal electrical activity. Using membrane potential dyes we found that spontaneous action potential firing can be detected using time-lapse confocal microscopy. Initially, patch clamp recording techniques were used to verify spontaneous electrical activity in GH4\C1 pituitary cells. It was found that serum depleted cells had reduced spontaneous electrical activity. Brief exposure to the serum derived growth factor, IGF-1, reconstituted electrical activity. We have examined the possibility of developing a rapid fluorescent assay to measure neuronal activity using membrane potential dyes. This neuronal regeneration assay has been adapted to run on a confocal microscope. Quantitative fluorescence is then used to measure a compounds ability to regenerate neuronal firing.The membrane potential dye di-8-ANEPPS was selected for these experiments. Di-8- ANEPPS is internalized slowly, has a high signal to noise ratio (40:1), has a linear fluorescent response to change in voltage.

Fluorescent potentiometric dyes for membrane-potential imaging

1994 ◽  
Vol 52 ◽  
pp. 166-167
Author(s):  
Leslie M. Loew
Keyword(s):  
Membrane Potential ◽  
Single Cells ◽  
Quantitative Imaging ◽  
Optical Recording ◽  
Biological Processes ◽  
Major Focus ◽  
The Past ◽  
Excitable Systems ◽  
Major Application ◽  
The Impact

A major application of potentiometric dyes has been the multisite optical recording of electrical activity in excitable systems. After being championed by L.B. Cohen and his colleagues for the past 20 years, the impact of this technology is rapidly being felt and is spreading to an increasing number of neuroscience laboratories. A second class of experiments involves using dyes to image membrane potential distributions in single cells by digital imaging microscopy - a major focus of this lab. These studies usually do not require the temporal resolution of multisite optical recording, being primarily focussed on slow cell biological processes, and therefore can achieve much higher spatial resolution. We have developed 2 methods for quantitative imaging of membrane potential. One method uses dual wavelength imaging of membrane-staining dyes and the other uses quantitative 3D imaging of a fluorescent lipophilic cation; the dyes used in each case were synthesized for this purpose in this laboratory.

Effects of Gender, Parental Role, and Time on Infant- and Adult-Directed Read and Spontaneous Speech

2019 ◽  
Vol 62 (11) ◽  
pp. 4001-4014
Author(s):  
Melanie Weirich ◽  
Adrian Simpson
Keyword(s):  
Parental Involvement ◽  
Gender Identity ◽  
Spontaneous Speech ◽  
First Year ◽  
Space Size ◽  
Vowel Space ◽  
Potential Impact ◽  
Phonetic Features ◽  
And Gender ◽  
Description Task

Purpose The study sets out to investigate inter- and intraspeaker variation in German infant-directed speech (IDS) and considers the potential impact that the factors gender, parental involvement, and speech material (read vs. spontaneous speech) may have. In addition, we analyze data from 3 time points prior to and after the birth of the child to examine potential changes in the features of IDS and, particularly also, of adult-directed speech (ADS). Here, the gender identity of a speaker is considered as an additional factor. Method IDS and ADS data from 34 participants (15 mothers, 19 fathers) is gathered by means of a reading and a picture description task. For IDS, 2 recordings were made when the baby was approximately 6 and 9 months old, respectively. For ADS, an additional recording was made before the baby was born. Phonetic analyses comprise mean fundamental frequency (f0), variation in f0, the 1st 2 formants measured in /i: ɛ a u:/, and the vowel space size. Moreover, social and behavioral data were gathered regarding parental involvement and gender identity. Results German IDS is characterized by an increase in mean f0, a larger variation in f0, vowel- and formant-specific differences, and a larger acoustic vowel space. No effect of gender or parental involvement was found. Also, the phonetic features of IDS were found in both spontaneous and read speech. Regarding ADS, changes in vowel space size in some of the fathers and in mean f0 in mothers were found. Conclusion Phonetic features of German IDS are robust with respect to the factors gender, parental involvement, speech material (read vs. spontaneous speech), and time. Some phonetic features of ADS changed within the child's first year depending on gender and parental involvement/gender identity. Thus, further research on IDS needs to address also potential changes in ADS.

Exploring the Potential Impact of Sentence-Level Comprehension and Sentence-Level Fluency on Deaf Students' Passage Comprehension

2020 ◽  
Vol 63 (7) ◽  
pp. 2281-2292
Author(s):  
Ying Zhao ◽  
Xinchun Wu ◽  
Hongjun Chen ◽  
Peng Sun ◽  
Ruibo Xie ◽  
...  
Keyword(s):  
Independent Predictor ◽  
Vocabulary Knowledge ◽  
Group Differences ◽  
Regression Analyses ◽  
Deaf Students ◽  
Mediating Role ◽  
Sentence Level ◽  
Mediating Mechanisms ◽  
Potential Impact ◽  
The Relationship

Purpose This exploratory study aimed to investigate the potential impact of sentence-level comprehension and sentence-level fluency on passage comprehension of deaf students in elementary school. Method A total of 159 deaf students, 65 students ( M age = 13.46 years) in Grades 3 and 4 and 94 students ( M age = 14.95 years) in Grades 5 and 6, were assessed for nonverbal intelligence, vocabulary knowledge, sentence-level comprehension, sentence-level fluency, and passage comprehension. Group differences were examined using t tests, whereas the predictive and mediating mechanisms were examined using regression modeling. Results The regression analyses showed that the effect of sentence-level comprehension on passage comprehension was not significant, whereas sentence-level fluency was an independent predictor in Grades 3–4. Sentence-level comprehension and fluency contributed significant variance to passage comprehension in Grades 5–6. Sentence-level fluency fully mediated the influence of sentence-level comprehension on passage comprehension in Grades 3–4, playing a partial mediating role in Grades 5–6. Conclusions The relative contributions of sentence-level comprehension and fluency to deaf students' passage comprehension varied, and sentence-level fluency mediated the relationship between sentence-level comprehension and passage comprehension.

The System of Technical Regulation in Russia: The Possible and Expected Impact on Competition

2009 ◽  
pp. 110-123
Author(s):  
P. Kryuchkova
Keyword(s):  
Russian Federation ◽  
Technical Regulation ◽  
Russian Economy ◽  
Regulation Reform ◽  
Potential Impact

The article considers the development of the technical regulation reform in Russian Federation and the potential impact of technical regulation on competition and competitiveness of industries and the Russian economy as a whole. It concludes that the reform has been actually reduced, and it is demanded for in the framework of the modernization scenario of Russia’s economy development.

Theoretical and Empirical Research in Modern Economics: Problems of Communication

2008 ◽  
pp. 4-19 ◽  
Author(s):  
A. Libman
Keyword(s):  
Empirical Research ◽  
Econometric Methods ◽  
Potential Impact ◽  
Empirical Turn

The last decades witnessed the increasing importance of econometric methods and empirical research in economics. The success of the empirical turn in economics depends on the formats and problems of communication between theory and empirics. The paper considers potential difficulties in communication "from the theory to empirical research" and "from empirical research to theory". It analyzes the role of informal consensus as an instrument facilitating such communication and potential impact of this consensus on the direction of research.

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